High-pressure steam generator



fluvenov: W/L HELM BEYE/z vorney.

W. BEYER PRESSURE STEAM GENERATOR Filed Sept. 28, 1938 .a .El

Aug. 3l, 1943.

Patented Aug. 31, 1943 UNITED ISTATES PATENT `OFFICE Wilhelm Beyer, Berlin-Frohnau, Germany; vested in the Alien Property Custodian Application September 28, 1938, Serial No. 232,062 In Germany September 30, 1937 3 Claims.

The present invention relates to high-pressure steam generators in which superheated steam, serving as the heat carrier, is blown by way of nozzles into the water space of boiler drums. In steam generators of this kind, particularly if they work with chemically prepared feed water only or with a high concentration of the boiler water, corrosions may be caused at the nozzles admitting superheated steam. Such corrosions are according to this invention prevented by the fact that water is introduced into the nozzles near their inlet end.

The invention is based on the knowledge that corrosions are not or not alone due to the presence of special properties of the boiler water, but are in any case in a high degree duc to the fact, that the walls. of the nozzles have a rather high temperature. By means of this invention the interior of the nozzles is protected against the high temperatures of the entering steam. On the one hand, the superheated steam is already cooled when reaching the nozzles, and on the other hand a water film may be formed along the walls of the nozzles, which prevents direct contact of the superheated steam with the walls of the nozzle.

Feed water or boiler water, or feed water and boiler water together may be introduced into the interior of the nozzles. In particular, if boiler water is used for this purpose, the quantity of water introduced into the nozzles may be maintained in great excess with regard to the superheated steam.

Of course, with the arrangement according to this invention a substantial quantity of steam is generated in the nozzles themselves. Hereby the further advantage is obtained, that a very low level of water may be maintained in the boiler drum, resulting in a great height of steam space. Another advantage is, that the scale reaching in the nozzles cannot stick to the nozzles, thereby tending to maintain uniform operation of all nozzles and the perfect utilization of the total volume of the drum.

In the accompanying drawing some embodiments of the invention are shown by way of eX- ample.

In the drawing:

Fig. 1 is a longitudinal section through an encased nozzle into the interior of which feed water also is introduced,

Fig. 2 illustrates a longitudinal section through a nozzle the walls of which are protected by boiler water,

Fig. 3 shows a more or less diagrammatic cross section through a boiler having nozzles according to Fig. 3, and

Fig. 4 is a longitudinal section through a nozzle using simultaneously feed Water and boiler water.

According to the construction shown in Fig. 1, the nozzle la secured to the socket 2a is provided with a single slot 3a which extends over the entire circumference of the nozzle. For the purpose of forming a water film along the interior walls of the nozzle la the slot 3a, is, with regard to the direction of flow of the water, arranged in the longitudinal direction of the nozzle la. By a slight injector-like formation of the inletl end of the nozzle la with the slot the distribution of the feed water over the individual nozzles la in accordance with the admission of superheated steam to them may be assisted.

The annular channel 4a for feeding the water is extended in the form of a casing 6 over the main portion of the nozzle la, and the pipe connection 5a is connected to the casing B near the outlet end of the nozzle la. By this construction the feed water flowing towards the slot 3a simultaneously serves for cooling the outer surface of the wall of the nozzle la.

At the inlet end of the nozzle la a special insertion l' is provided which is screwed into the socket 2a and projects into the nozzle as far as to the slot 3a, a radiall clearance being left between the outer wall of said insertion and the inner wall of the nozzle la. This construction perfectly prevents superheated steam from contacting any point of the nozzle la, and the heat flow towards the walls of the nozzles also is checked. The space between the insertion 'l and the nozzle la is, during operation, filled with steam, so that the insertion 'l is prevented from coming into contact simultaneously with the steam of high temperature and with water and, therefore, is perfectly protected itself against corrosion.

For the purpose of using boiler water in connection` with the nozzle lb, shown in Fig. 2 and similar in construction to that illustrated in Fig. 1, the inlet end of this nozzle is, by correspondingly shaping the insertion lb with the slot 3b, formed in the manner of a steam jet pump, and the annular channel 4b is connected to the water space of the boiler drum. This connection again is formed as a casing 6b around the nozzle lb and ends at a certain distance above the nozzle Ib into the water space of the boiler drum. To enable sucking in of the boiler water, the portion of the nozzle I b serving to directly carry steam over its entire length covered by the walls of the nozzle against contact with the water.

As shown in Fig. 3, the feed Water is introduced into the boiler drum preferably near the discharge end of the individual nozzles lo used to blow in superheated steam, the arrangement being such, that in front of the discharge end of each nozzle Ib a smaller concentration of the boiler water occurs than in the remaining water space of the boiler drum. Fig. 3 shows a boiler drum 9 in the steam space of which the main feed pipe l0 for the superheated steam is arranged. This pipe i0 is provided with the sockets 2b to which the nozzles lb are connected which extend vertically downwardly. Each superheated steam nozzle ih is associated with a feed water nozzle Il. These feed water nozzles Il, which are connected to the feed pipe i2 and are of fan-shaped formation, are so arranged, that in front of each superheated steam nozzle lb a flow of fresh feed water spread. The water sucked into the nozzles ib then also has a lower concentration than the boiler water and eventually also is of lower temperature.

The nozzle shown in Fig. 4 represents a combination of the constructions shown in Figs. l and 2. The nozzle is provided with two slots 3c and 3c and associated annular channels 4c and 4c for the simultaneous use of feed water and boiler water. The feed water slot 3c which is formed by the insertion I3 and the superheated steam insertion 'fc is, by means or the annular channel 4c and the casing 6c, connected to the water space of the boiler drum and provided with the slot 3c in the manner of a water injector. For this purpose the slot 3c is arranged above the boiler water slot 3c" and concentratically to the latter'. The superheated steam insertion lc is again formed in such a manner that the flow oi' superheated steam additionaily acts in the manner of an injector.

What I claim is:

l. A high pressure steam generator comprising a boiler drum having a steam and a water space, a steam supply main in said boiler drum, an injector for blowing superheated steam into the said water space, means connecting the said steam main and the injector, the latter including an injector steam inlet section and a lower steam conducting section, said sections meeting in the plane of their smallest diameter and expanding from said plane in an upward and in a downward direction, means to position the said steam inlet section above the boiler water level and the lower section extending into the boiler water, a tubular insert connected to the'steam main and extending into the said upper steam inlet section, a

casing carried by the said steam main surrounding said injector and connected with a source of water supply, the lower edge of the casing being situated at a higher level than the lower edge of the injector tube and an annular slot between said insert and said upper steam inlet section for the supply of water from said casing to the inner surface of the said injector tube.

2. A high pressure steam generator comprising a boiler drum having a steam and a wa-ter space, a steam supply main in said boiler drum, an injector for blowing superheated steam into the said water space, means connecting the 'said steam main and the injector, the latter including an injector tube consisting of a comparatively short upper steam inlet section and a lower steam conducting section, said sections meeting in the plane of their smallest diameter and expanding from said plane in an upward and in a downward direction, means to position the said steam inlet section above the boiler water level and the lower section extending into the boiler water, a tubular insert connected to the steam main and extending into the said upper steam inlet section, a casing carried by the said steam main surrounding said injector and connected with a source of water supply, a cooling chamber in the upper part of said casing surrounding said tubular insert and an annular slot between said insert and said upper steam inlet section for the supply of water from said casing to the inner surface oi the said injector tube.

3. A high pressure steam generator comprising a boiler drum having a steam and a water space, a steam supply main in said boiler drum, an injector for blowing superheated steam into the said water space, means connecting the said steam main and the injector, the latter including an injector tube, the said tube consisting of a comparatively short upper steam inlet section and a lower steam conducting section, said sections meeting in the plane of their smallest diameter and expanding from said plane in an upward and in a downward direction, means to position the said steam inlet section above the boiler water level and the lower section extending into the boiler water, a tubular insert connected to the steam main and extending into the said upper steam inlet section, a casing carried by the said steam main, surrounding said injector, an annular slot between said tubular insert and said upper steam inlet section for the supply of water to the inner surface of the seid injector tube, an annular projection extending inwardly and downwardly from the inner wall of said casing into said annular slot dividing the said casing into an upper and a lower chamber and the said annular slot two superposed concentrical sub-slots, the upper chamber being connected to a feed water supply and the lower chamber being connected with the said boiler water space, the upper sub-slot connecting the upper chamber and the lower sub-slot connecting the lower chamber with the inner space of the upper steam inlet section of the said injector tube.

WILHELM BEYER. 

